Liz Cheney , whose upstart bid to unseat Wyoming Sen. Mike Enzi sparked warfare in the Republican Party and within her own family , is dropping out of the primary race , she said on Monday .

`` Serious health issues have recently arisen in our family , and under the circumstances , I have decided to discontinue my campaign , '' the eldest daughter of former Vice President Dick Cheney said in a written statement .

Cheney , 47 , began telling associates of her decision over the weekend , CNN reported Sunday night .

She was not specific about the health issues involved in her decision . But CNN has learned from multiple sources close to the family that they involve at least one of her children .

`` Though this campaign stops today , my commitment to keep fighting with you and your families for the fundamental values that have made this nation and Wyoming great will never stop , '' she added .

Cheney called Enzi , 69 , about her decision to bow out .

`` I talked to her first thing this morning . It was very nice that she called me , '' he told CNN on Capitol Hill , adding that he respects Cheney 's decision and that `` she and her family are in our prayers . ''

Asked if he was relieved that she was no longer in the race , he said he has n't `` had a chance to reflect on that yet . ''

Cheney 's surprising decision to jump into the race , an announcement made in a YouTube video last summer , roiled Republican politics in Wyoming , a state that her father represented in Congress for five terms in the 1970s and 80s .

Enzi is a low-key presence in Washington in the Senate . He was elected in 1996 and has amassed a conservative voting record with few blemishes .

He expressed public annoyance at Cheney 's decision to mount a primary challenge .

A number of his Senate colleagues quickly rallied to his side and pledged support for his re-election bid .

There was little public polling of the race , but two partisan polls released last year showed Enzi with a wide lead , an assessment mostly shared by GOP insiders watching the race .

In a statement after her announcement to drop out , the Wyoming Republican Party praised Liz Cheney for being a `` stalwart supporter '' and fundraiser for Wyoming candidates and county parties in the past .

`` Liz is a rising star in Wyoming and national politics and we look forward to her return when the time is right for her and her family , '' the statement read .

Cheney 's campaign got off to a rocky start .

Her critics labeled her a carpetbagger , noting that she moved to Wyoming only in 2012 after relocating from Virginia . The issue flared in August after the Wyoming media reported that Cheney improperly received a fishing license despite not living in the state for at least a year , as the law requires .

Grabbing even more attention was her very public dispute with her sister , Mary , over the issue of same-sex marriage .

Mary Cheney , who is a lesbian , took to Facebook in November to object to Liz Cheney 's opposition to same-sex marriage , claiming that her sister has previously supported her relationship while saying something very different on the campaign trail .

The dispute prompted their parents to weigh in , saying they were `` pained '' to see the sisters battle over a private matter in full view of the news media .

Beyond the campaign missteps , Cheney 's election effort , vigorously supported by her father and his allies , often felt out of tune with the small-government conservative sentiment that has fueled other Republican primary challengers .

Cheney , like her father , is an unapologetic neoconservative who favors muscular use of American military power overseas , a policy that does not sit well with many grassroots conservatives , particularly in the libertarian-leaning West .

Cheney ` surprised ' by public spat between daughters

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Cheney releases a statement citing `` serious health issues '' in her family

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Wyoming Sen. Mike Enzi first won the Senate seat in 1996

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The contest caused bitter feelings in the Republican Party and the Cheney family

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Enzi and Cheney speak by phone ; he says he respects her decision